Fixes incremental verification when the commit queue crashes.

pending_manager.py

Index: pending_manager.py
diff --git a/pending_manager.py b/pending_manager.py
index 5dd586d6f71172242bbf423e325dd349dba30776..7653a9f35ec18f511b29782bb67bc76ee60917a0 100644
--- a/pending_manager.py
+++ b/pending_manager.py
@@ -79,7 +79,10 @@ class PendingCommit(base.Verified):
     Returns True if all Verifiers were run.
     """
     for verifier in verifiers:
-      assert verifier.name not in self.verifications
+      if verifier.name in self.verifications:
+        logging.warning(
+            'Re-running verififer %s for issue %s' % (
+                verifier.name, self.issue))
       verifier.verify(self, revision)
       assert verifier.name in self.verifications
       if self.get_state() == base.IGNORED:
@@ -161,12 +164,17 @@ class PendingManager(object):
 
   def process_new_pending_commit(self):
     """Starts verification on newly found pending commits."""
+    expected = set(i.name for i in self.all_verifiers)
     for pending in self.queue.pending_commits[:]:
       try:
-        if (len(pending.verifications) == len(self.all_verifiers) or
-            pending.get_state() != base.PROCESSING):
+        # Take in account the case where a verifier was removed.
+        done = set(pending.verifications.keys())
+        missing = expected - done
+        if (not missing or pending.get_state() != base.PROCESSING):
           continue
-        logging.info('Processing issue %s' % pending.issue)
+        logging.info(
+            'Processing issue %s (%s, %d)' % (
+                pending.issue, missing, pending.get_state()))
 
         revision = self.checkout.prepare()
         if pending.verify(revision, self.pre_patch_verifiers):